RESUMEN
BACKGROUND: Prognostic factors for patients with stage III melanoma are still controversial. METHODS: Two hundred eighty-six patients with solitary cutaneous malignant melanoma of the skin in Stage III (International Union Against Cancer [UICC]) were followed up for as long as 11 years. RESULTS: Patients in risk group pT 4a, pN O (primary tumor thickness of more than 4 mm or invasion of subcutis and absence of regional lymph node metastasis in elective lymph node specimen) have a 5-year survival rate of 72.8%. If regional metastases are excluded clinically (pT 4a, NO), the 5-year survival rate is 62.8%. Patients with regional lymph node metastases have an average 5-year survival rate of 39%, depending mainly on the number of involved lymph nodes and the depth infiltration of the primary tumor. The number of involved lymph nodes reflects the grade of dissemination. It shows a stronger correlation with the prognosis than does the size of metastases. CONCLUSIONS: The authors recommend that revisions of the UICC classification should distinguish Stage IIIA and IIIB based on the presence or absence of regional metastases and that a clearer distinction should be made between regional cutaneous or subcutaneous metastases and regional lymph node metastases.